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Öğe Application of industry 4.0 on biomass liquefaction study: A case study(Elsevier B.V., 2019) Koyuno?lu C.; Karaca H.Biomass crude oil generation technology is currently up-to-date in terms of reducing emissions. However, the studies are mostly considered as an alternative to aviation, sea and automative transportation vehicles added to the fuel mixture and are among the new technologies to reduce CO2 emissions such as global warming and reduction of greenhouse gases. The rate of production of crude biofuels obtained from biomass, a renewable energy source, according to a reactor size determined by industry 4.0 will be determined using Ansys software in this study. The simulation program to be used shall be made with the mixer module of the ansys software. Our modeling study, which is based on the data obtained from the literature, is about the verification of the reactions with simulation values. The simulation values we make to ensure the correct solid distribution in the reactor are important for the formation of the correct reaction conditions. The production of liquid fuel from biomass cannot go beyond pilot scale trials. Apart from this, many fuel tests are expensive, mostly due to the withdrawal of investors from feasibility studies. In the design of the factory, industry 4.0 applications provide a solution that will provide the cheapest installation cost of all fuel tests, as well as facilitating the repayment of the investment cost. Beyond that, it will not be wrong to say that the actual data will give direction to the correct operation conditions. Ansys software emphasizes the use of a stirred tank reactor in this study as a tool for modeling an experimental method as well as for pilot and industrial applications. © 2019 The Authors. Published by Elsevier B.V.Öğe Batch Reactor Modeling and Simulation by MATLAB for Clean Coal Technologies: A First Order Kinetic Modelling Approaches(International Pittsburgh Coal Conference, 2023) Koyunoğlu C.; Karaca H.This study presents a numerical calculation method to investigate the co-liquefaction of coal and biomass in a batch reactor. The primary objective is to determine the concentrations of different components under varying types of coal and biomass, facilitating the selection of optimal batching options based on reactor capacity. The kinetic model is developed by amalgamating literature data, preliminary experiments, and fundamental principles of reaction kinetics. The co-liquefaction process is represented as a series of first-order reactions involving two reactants: coal and biomass. The core of the model consists of coupled differential equations that describe the rate of change of coal and biomass concentrations over time. The rate of change is directly proportional to the concentration of each reactant, scaled by a reaction rate constant `k`. To address these non-linear differential equations, the MATLAB `ode45` function, employing the Runge-Kutta method suitable for non-linear systems, is utilized. The reaction rate constant `k` is estimated through experimental data, where the experimental concentration-time profiles are fitted to the model's predictions. Model validation is accomplished by comparing its predictions against experimental conditions not used in parameter estimation. Statistical metrics such as the correlation coefficient and root mean square error (RMSE) are used to assess the goodness of fit. Additionally, a sensitivity analysis is conducted to examine the impact of various parameters on the model's predictions. This involves varying the initial concentrations of coal and biomass, the reaction rate constant `k`, and other pertinent parameters relevant to the co-liquefaction process. To enhance accessibility, a MATLAB-based Graphical User Interface (GUI) is developed, enabling researchers and industry professionals to input experimental conditions, conduct simulations, and visualize real-time results. It should be noted that the values of reaction rate constants, `k1`, `k2`, `k3`, `k4`, `k5`, and `k6`, are assumed for illustrative purposes and should be adjusted based on experimental data for specific reactions. The simulations offer insights into the concentration profiles of the reactants and products over time. Overall, this study significantly contributes to the understanding of the co-liquefaction process of coal and biomass, paving the way for the design of an efficient plant infrastructure based on the components that yield the highest total conversion due to the first-order reaction kinetics. © 2023 40th Annual International Pittsburgh Coal Conference, PCC 2023. All rights reserved.Öğe Chemical Desulfurization of Low-Rank Muğla-Yatağan and Kütahya-Tunçbilek Lignites(International Pittsburgh Coal Conference, 2023) Gündüz F.; Karaca H.Impurities present in coal structures, when combusted, release harmful emissions into the environment. Sulfur is a primary impurity in this context. One of the most effective methods for removing inorganic materials from lignite, a type of coal, is chemical desulfurization. In this study, lignite samples from two different reserves in Turkey were treated with H2O2 and H2SO4 reagents at varying temperatures, reagent concentrations, and durations to examine sulfur removal. According to the results obtained, the sulfur removal rates for Tunçbilek and Yatağan lignites were found to be 31.81% and 48.12% respectively at 30% H2O2 concentration, and 32.12% and 57.14% respectively at 30% H2O2 and 0.1 N H2SO4 concentrations. As the concentration of the chemical reagent increased, sulfur removal also increased. In a 20% H2O2 solution under process conditions of 30-90 minutes, pyritic sulfur in Tunçbilek lignite decreased from 0.73% to 0.21%, and in Yatağan lignite, it decreased from 0.43% to 0.20%. In the desulfurization process conducted at 50°C with H2O2 reagent, the sulfatic sulfur content in Tunçbilek and Yatağan lignites was obtained as 0.21% and 0.07% respectively. The method used in this study proved effective in removing sulfur from low-rank lignites. It is considered an effective method to reduce the harmful effects of sulfur on the environment. © 2023 40th Annual International Pittsburgh Coal Conference, PCC 2023. All rights reserved.Öğe Desulphurization kinetics of number 6 fuel oil via a chemical method(2005) Karaca H.; Yildiz Z.The effect of reaction temperature and reaction time on desulfurization of No. 6 fuel oil with the H2O2/H2SO4 method was studied and then a kinetic expression definition on desulfurization was tried. The maximum desulfurization was performed at conditions of reaction temperature of 40°-50°C and reaction time of 150 min. At higher reaction temperatures, the degree of desulfurization increased despite that the higher heating value of the sample decreased, because the fuel oil sample was oxidized much more by increasing the reaction temperature. As a result of kinetic approach, the approximate desulfurization degree of fuel oil by chemical method and the rate constant expression was 0.96 and k = 5.84 × 106 exp(-65.08/RT), respectively.Öğe Effect of Sodium Boron Hydride (NaBH4) on Waste Polyethylene Terephthalate Pyrolysis(Institute of Physics Publishing, 2019) Olam M.; Karaca H.Polyethylene terephthalate, which is used in many applications today, is very important in terms of nature and source in order to ensure recycling by appropriate methods after use. Because polyethylene terephthalate is a durable and long-lasting thermoplastic which is resistant to many environmental influences. Recovering residual plastics has become mandatory. In this study, the conversion of waste plastic to a new liquid fuel by polyethylene terephthalate (PET) pyrolysis method was investigated. Sodium boron hydride (NaBH4) was used as both catalyst and hydrogen donor in the pyrolysis experiments. Pyrolysis experiments were carried out in a batch reactor under catalytic and non-catalytic conditions, reaction time of 15-90 minutes, reaction temperature of 325-425 °C, solid/solvent ratio of 1/4 and initial nitrogen gas pressure of 20 bar. According to the results obtained, the most suitable reaction temperature was found to be 375-425 °C and the reaction time was 30 minutes. At the reaction times of 30 minutes, the maximum total conversion in non-catalytic conditions of waste polyethylene terephthalate samples was 53.1% at 400 °C reaction temperature and the highest oil + gas yield was 43.7% at 425 °C reaction temperature. In the pyrolysis of polyethylene terephthalate samples in the presence of sodium boron hydride, the maximum total conversion was 55.3% at 400 °C reaction temperature and the highest oil + gas yield was 44.6% at 425 °C reaction temperature. As a result, it can be argued that sodium boron hydride used in pyrolysis experiments of waste polyethylene terephthalate acts as both catalytic and hydrogen donor. © Published under licence by IOP Publishing Ltd.Öğe The reasons leading businesses to concordat and solution suggestions(IGI Global, 2023) Karaca H.There are many factors that lead businesses to bankruptcy. The risk environment created as a result of changes in some macroeconomic indicators such as exchange rates, interest rates, inflation, and financial instability as a result of the inability to manage risk properly cause businesses to go bankrupt or an economic crisis. The bankruptcy of a business imposes a cost not only on stakeholders, but on society as a whole. In this context, in order to ensure economic welfare and maintain the economic existence of enterprises, the function of the institution of concordat in the execution and bankruptcy law has been increased; the way of restructuring their debts in accordance with the final decision of the court in line with the consent of their creditors has been opened for the debtors. In the study, the institution of concordat was examined in outline, the reasons leading businesses to concordat were evaluated, and solution suggestions were developed. © 2023, IGI Global. All rights reserved.Öğe Synthesis of an innovative SF/NZVI catalyst and investigation of its effectiveness on bio-oil production in liquefaction process alongside other parameters(Springer, 2024) Ersöz K.; Bayrak B.; Gündüz F.; Karaca H.Today, new energy sources alternative to fossil fuels are needed to meet the increasing energy demand. It is becoming increasingly important to constitute new energy sources from waste biomass through the liquefaction process. In this study, walnut shells (WS) were liquefied catalytically and non-catalytically under different parameters using the liquefaction method. In this process, the effect of silica fume/nano zero-valent iron (SF/NZVI) catalysts on the conversion rates was investigated. The catalyst was synthesized by reducing NZVI using a liquid phase chemical reduction method on SF. The SF/NZVI catalyst was characterized by scanning electron microscopy- energy dispersive X-ray (SEM–EDX), transmission electron microscope (TEM), Brunauer–Emmett–Teller (BET), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analysis. The effect of various process parameters on the liquefaction process was investigated. In this context, the reaction temperature ranged from 300 to 400 °C, the solid/solvent ratio ranged from 1/1 to 1/3, the reaction time ranged from 30 to 90 min, and the catalyst concentration ranged from 1 to 6%. According to the results obtained, the most suitable operating conditions for non-catalytic experiments in liquefaction of WS were found to be temperature of 400 °C, reaction time of 60 min, and solid/solvent of 1/3. In catalytic conditions, the optimum values were obtained as temperature of 375 °C, reaction time of 60 min, solid/solvent ratio of 1/3, and catalyst concentration of 6%. The highest total conversion and (oil + gas) % conversion were 90.4% and 46.7% under non-catalytic conditions and 90.7% and 62.3% under catalytic conditions, respectively. Gas chromatography/mass spectrometry (GC/MS) analysis revealed the bio-oil was mainly composed of aromatic compounds (benzene, butyl-, indane and their derivatives,) and polyaromatic compounds (naphthalene, decahydro-, cis-, naphthalene, 1-methyl-.). The aim of increasing the quantity and quality of the light liquid product in the study has been achieved. © The Author(s) 2024.
